Fig. 2a. Anomaly correlation for 500-hPa geopotential, Northern Hemisphere (20-80N) as a function of forecast length, for forecasts verifying 10 Oct 2001 - 15 Apr 2002. MRF(black) is current model, MRFX(blue) the new model and EC(red) is ECMWF model. Inset is for various zonal wave numbers.